I bought a laser pen a while ago with a wavelength of 650nm. What do you mean?

The wavelength of 650nm means that the wavelength of light emitted by this laser pen is within a narrow range of about 650nm. The laser emitted at this wavelength is red light.

The colors of light refracted by different wavelengths will be different. Other wavelengths and colors of the laser are as follows:

The wavelengths are 5 15-520nm and 532nm, which emit green light;

The wavelength is 445 ~ 450 nm, and it emits blue light;

At the wavelength of 405nm, it emits purple light;

Extended data:

A, the use of other color laser pen:

1, green laser pointer

Green laser pointer can have a variety of output power, even at low power, it can be seen at night, so it is often used by astronomy enthusiasts to point out stars and constellations.

2. Blue laser pointer

The power of 473nm blue laser is too low and unstable to be widely used. Until later, a blue laser diode with power exceeding 1000mW and wavelength of 445nm was developed, and the blue laser pen was mass-produced and popularized.

3. Purple laser pointer

Purple with a wavelength of 405nm is close to the ultraviolet band, and its visibility is low, but it can stimulate fluorescence, so it is often used for banknote inspection and chemical inspection.

Second, the use of laser pointer matters needing attention:

1, laser pointer may cause serious damage to retina and macula, so it is not suitable for children.

2. It is not suitable to use laser pens in art galleries, because some paintings may be afraid of light.

3. Laser pens should not be used for solid objects sensitive to temperature, because some high-power laser pens will have obvious thermal effects.

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